Snow King is correct. Diesel prices are supply and demand (refineries going off line, winter heating oil etc)and speculators driving prices. Prices went sky high and were projected to go higher by speculators playing on fears of war with Iran -that didn't happen and prices dropped. Diesel/gas prices in the US are cheapest on the planet except in countries where the gov heavily subsidizes (pemex). Many in other countries would say you are very lucky indeed. Enjoy it while it lasts. Myths are fun, facts are boring.